Netty up to 4.1.135.Final/4.2.15.Final SpdyFrameCodec allocation of resources

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.56

Summaryinfo

A vulnerability classified as problematic was found in Netty up to 4.1.135.Final/4.2.15.Final. This affects an unknown part of the component SpdyFrameCodec. Executing a manipulation can lead to allocation of resources. This vulnerability is registered as CVE-2026-55833. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability classified as problematic was found in Netty up to 4.1.135.Final/4.2.15.Final. This vulnerability affects an unknown function of the component SpdyFrameCodec. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. As an impact it is known to affect availability. CVE summarizes:

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty SPDY header decoding continues inflating zlib-compressed header blocks after the raw header parser has exceeded `maxHeaderSize` and marked the frame truncated in `SpdyFrameCodec`, allowing a remote peer to send a small compressed `HEADERS` block that expands into much larger raw header data and causes compression-amplified CPU and allocation churn. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-55833 since 06/17/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 4.1.136.Final or 4.2.16.Final eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Netty 4.1.136.Final/4.2.16.Final

Timelineinfo

06/17/2026 CVE reserved
07/20/2026 +33 days VulDB entry created
07/21/2026 +0 days Advisory disclosed
07/21/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-55833 (🔒)
GCVE (CVE): GCVE-0-2026-55833
GCVE (VulDB): GCVE-100-380800

Entryinfo

Created: 07/21/2026 01:42
Changes: 07/21/2026 01:42 (52)
Complete: 🔍
Cache ID: 216::103

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